Process of desulfurizing and subsequent smelting.



N0. 852,612. PATENTED MAY 7, 1907.

' W. G. PERKINS. PROCESS OF DESULFURIZING AND SUBSEQUENT SMELTING.

APPLICATION FILED JAN. 22, 1906.

UNITE SATES' PAENT @FFTQE.

.WALTER e. rename, or SAN FRANCISCO, CALIFORNIA.

A success or DESULFUREZINGAND suessoosnr SMELTING.

Specification of Letters Patent.

Patented May '7 1907.

Application filed January 22, 1906. Serial No. 297,354.

To (Jail whom it may concern:

Be it known that I, WALTER G. PERKINS, a subject of theKing of Great Britain, resid ing at San Francisco, in the county of San Francisco and State of Qalifornia, have invented cer'tain new and useful Improvements in Processes of Desulfurization and Subsequent Smelting, of which the following is a specification.

This invention relates to the treatment of metalliferous substances and chemical compounds by heat, and more particularly to a process of desulfurizing, or roasting, "and smelting ores, concentrates, matte, or any other mineral or chemical substance in one continuous operation by means of a liquid or gaseous fuel, together with the combustible material in the ore itself.

The present invention is particularly adapted tothe smelting of pyritic ore in a finely divided state, and concentrates such as are the products of the various concentrating tables, a large percentage of which may pass a screen of 200 mesh to the inch. Material such as this is extremely dii'licult to treat even. by the universally used method of first desulfurizing in any of the/turret or reverberatory roasting furnace and then smelting the calcuncd material in a reverberatory smelting furnace, making two stages of the process and consequently the handling of the material a second time, which entails losses in values and extra expense. During the roasting process there are large losses in the form of flue dust caused by the. air current going through the furnace and takingwith it a large percentage of the finely divided material which has to be collected in large dust settling chambers at almost a prohibitive expense; this will be almost entirely averted by my process because there will always be a high column or volume of charge above the twyer zone where the air enters and where the desulfurization is taking place. The actual smelting operationdoes not take place in this receptacle, but merely the desulfurizing, the charge descending to the throat of the lower receptacle before becoming thoroughly fused and in a sul'liciently molten form for the matte to separate from the slag.

The drawing submitted embodying a form of apparatus capable of carrying out the process described is in accordance with the examiners requirement.

In this drawing Figure 1 is a vertical sec-- tion; Fig. 2 is a lon itudinal view of a portion of the furnace taken at right angles to Flg. 1. p

In the drawing 1 indicates the stack or main portion of the furnace, which may be of theusual size and style, and around which is arranged a wind-130x 2 which communicates with the interior of the stack through twyers or passages 3. Beneath the-stack is a hollow'crucible, which is preferably removable, and which is adapted'to be separately heated by gaseous or atomized fuel introduced directly into it. tracted at the top so as to form a throat in which the. actual smelting operation'takes ace. the gaseous or other fuel is introduced into The crucible is con'-- the hollow crucible independently of the;

smelting zone and is allowed and permitted to expand and attain a full combustion, which it could not if introduced directly into a mass of. finelydivided material. In'such a case, the gaseous fuel, having no oppor tunity to expand and to receive the necessary oxygen iorperfect combustion, will simply back out and become inert. When the individual pieces of material are of comparatively large size, interstices between the members of the mass, may permit the expansion and combustion of a gaseous or atomized fuel; but such a fuel introduced directly into a mass of very finely divided material, cannot do effective work for the reasons before stated. But with my process the steps are continuous, whereby the heat is con served and utilized, and the movement of the material is automatic and by gravity, which reduces the cost of handling and treatment to the minimum. Another advantage arising from my process is the ease with which the temperature can be controlled, in contr distinction to the non-fuel pyritic or the added solid fuel of the semi-pyritic smelting processes, thereby making it possible to treat extremely refractory ores which require temperatures higher than can be obtained in pyritic or semi-pvritic smelting, because if more air is supplied to apyritic smelting furnace than can combine with the elements it will decrease the temperature of the mass and cause the furnace to become cold or freeze, and if solid fuel be fed to the furnace with the ore, as in semi-pyritic smelting, there is danger of the temperature of the mass rising above the smelting zone to sucha degree as to cause overnre of the top of the material in furnace and lowering of the temperature at IIO 7 It will therefore be understood. that the bottom or smelting zone, which causes a furnace to run badly. Furthermore, by

not havin a quantity of carbonaceous solid fuel mixe' with the material to be smelted,

the air blown into the charge through the twyers' or wind box is used entirely for oxidicing the elements in the charge and is not consumed by the carbon of the solid fuel to generate heat for carrying on the operation, as in scmi-pyritic smelting. The foreign heat being supplied by or oil with an air blast of its own, would give practically a neu tral atmosphere, as in reverberatory furnace smelting, and would, after expending itself on the smelting, render excess available to ascend into the charge above to supply the requisite heat to carry on the chemical reao tion between the elements in the charge and the air supplied. through the twyers. it also has the advantage of keeping the smelting zone at one point in the furnace shaft, thereby preventing the danger of overfiraf which cannot be controlled when solid car bonaceous fuel is'mixed with the charge, as

the point of,.hision rises and lowers accord ing to the condition of the furnace and causes most of the evils encountered in blast furnace smelting. Besides being able to control the heat when supplied from as or oil it is more economical and also avoi s the introduction of foreign substances into the charge in. the form of ash, etc, which would add much more to the dross from which the values must be separated. Still another advane tage is that asmelter can be operated at a point removed from transportation by the generation of producer gas from Wood, there by rendering the smelter independent oi a coal or coke supply, and there are very few points where either coal, oil or Wood cannot be obtained, either being used for making producer gas. 7

. In carrying out my process, the material to be roasted and smelted is'fed into a receptacle having placesin its sides, as a twyer or wind box, preferably near the bottom, for the admission of air, and an opening in the bottom for the escape of the material after it has been initially treated or desulfurized.

second receptacle is arranged directly below the first one into which said material falls by gravity. after it has become semi-lused or liquefied and in which the separation of the more valuable material from the takes met that the mass- 'plefely smelte seas is from the applied smelting heat in. the lower receptacle, will be sufiieient to-purify or desulturize the mass for further or iin'al treatrnent. I,

As the mass becomes heated and semiiused it will project down through the opening in the bottom of the upper receptacle into the lower receptacle, where it will be sub ected to a degree of heat sufficient to completely fuse or melt it and cause it to fall into the lower receptacle Where the valuable portions matte, or metal, which being heavier than the dross or sl ag, will settle in the bottom and from whence it can be removed in the ordinary manner, as by continuous overflow, etc.

".lhe heat from external sources is preferably obtained from an inflammable gas/or from fluid fuel as oil reduced to a gaseous form in; any well lmown manner, and it is applied entirely through the lower receptaole. W hen the process is originally started, the lower receptacle will be empty, and the heat will pass through the openingin the bottom of the upper receptacle, into and up through the of material therein until it becomes hot enough to cause the sulfur. to burn and be eliminated therefrom; When the mass reaches such a degree oftem'peratore, air is admitted t on ,h the twyers in the sides of the receptacle. which will support the combustion. of the sulfur and cause a complete fusion of some of the mass and a aartial fusion of the less easily fused portions.

ihis semi-fused mass will then settle down to the bottom of the receptacle and partly protrude through the opening in the bottom thereof into the lower receptacle where it will be subjected to the full effect of the applied heat therein which will cause it to be completely fused or melted and drop through the opening into the lower receptacle. As the lower portion of the mass in the upper receptacle is thus melted and falls away, more of the mass will take its place and pro-' trude and in turn will be melted and fall away, thereby causing the. process to be continuous.

From the foregoing it will be seen that as the material is fed in at the top of the upper receptacle it gradually becomes heated as it passes downward, then ignites and assists in supplying the necessary heat to desulfurize or purify itself, and finally it passes down into the lower receptacle where it is comd and the valuable portions separated from the slag, The heatirom the desulfurizing process is utilized, also the heat from the gaseous fuel, because it has to pass up through the entire mass to find an ,exit, making iteconomical and quick to treat the material in a continuous process. The material to be treated maybe in any form, as. ores, concentrates, matte, etc, and is preferably fed in at the top, and the propore 01' Dy-pa e Where it W112 be 012th Lhe lngoing an and. ehereby in this manner the heeimg be venue :1 either at the 1 the wind box, 01' 130 311, n #1 n an I l A w qt [1 0 0 1*: CLQL dildo til/Luv U W 111% (unable xesa bu Wlth. different Kinds 0t ores 01' substances.

, described my invention, what 1 and. desire $0 seeme by Letters 20 is:

The of wee-ting ores in a, finely divided which csnsist-s in introducing gaseous fuel mm a heated space below the smelting zene and. than passing said fuel 2 5 mixed with air up threugh the smelting zone and at the same time introducing air into the smelting zone.

in i/ ESKJLDOQY enerem 1 have atfixed my s gnature, in presence of awe Witnesses, this 0 15th day 0f Jenner 1906.

WALTER G. ?ERKI;NS.

VJitnesses M. R. SEELY,

F. "L BARTEII. 

